My nights all feel like I have no dream at all, but then in the last few instants of sleep, my mind throws together a massive story which combines all of the unrelated details that I have focussed on in the last week or so. If I wake before this instant, I remember nothing. If I wake after this instant, I remember what feels like a dream that took hours. If I awake right during those few dream creation seconds, my dream feels like it was abrupted, unfinished.
I don't know if that is what really happens, but that is what I always feel.
As an aside, naps suck for me. If I take a nap the rest of my day is 100% ruined. I never can fully awake and I'm dizzy, confused, and far more tired than I was before the nap. A 5 min nap, 15 min nap, 1 hour long nap, it doesn't matter. It makes me so absolutly miserable after a nap, I try to avoid them.